Package the rust_nonsecure keymint default HAL in an APEX

This will make it easier to swap in and out with the Cuttlefish remote
implementation.

Bug: 331474817
Test: m com.android.hardware.keymint.rust_nonsecure
Change-Id: I0e9a350b62a90ef6126db109195e19b4181d0cf8
diff --git a/security/keymint/aidl/default/file_contexts b/security/keymint/aidl/default/file_contexts
new file mode 100644
index 0000000..dce7e3c
--- /dev/null
+++ b/security/keymint/aidl/default/file_contexts
@@ -0,0 +1,3 @@
+(/.*)?                                                           u:object_r:vendor_file:s0
+/etc(/.*)?                                                       u:object_r:vendor_configs_file:s0
+/bin/hw/android\.hardware\.security\.keymint-service\.nonsecure  u:object_r:hal_keymint_rust_exec:s0